Proceedings of 2022 AOCS Annual Meeting & Expo
"Methyl ester sulphonates (MES), which are produced from renewable vegetable oil-based mater... more "Methyl ester sulphonates (MES), which are produced from renewable vegetable oil-based materials and have an ISO 16128 natural origin index of 0.84, are promising new surfactants for conditioning hair shampoos. Previous studies have shown that MES has low skin irritation potential (i.e., mild to the skin), provides easier deposition of conditioning agents compared to sodium lauryl ether sulphate (SLES), and readily delivers desired rheology profiles. A drawback of MES is that it has poor solubility at low temperatures. The Krafft temperatures (TK) of MES-C16 and MES-C18 are 28 °C and 41 °C, respectively, which can be lowered substantially by using eutectic mixtures of MES-C16 and MES-C18; for example, MES-C16/C18 (3:1, w/w) has a TK of 15 °C. At temperatures below 15 °C, all mixtures of MES-C16 and MES-C18 are turbid due to the formation of MES crystals, and phase separation could occur during long-term storage. The solubility of MES could be further improved by incorporating the MES molecules into the micelles of other surfactants. In this study, the solubility of MES in pure water at 5 °C in the presence of alkyl polyglucosides (APG) was investigated. The results showed that the solubility of MES improved by > 28 times in the presence of APG at low total surfactant concentrations and predicts that at higher total surfactant concentrations, solutions of MES and APG will remain transparent at 5 °C when the weight fraction of MES-C16, MES-C18, MES-C16/C18 (80:20), and MES-C16/C18 (60:40) are below 28 %, 15 %, 35 %, and 38 %, respectively. Predictions for MES-C16/C18 (80:20) and MES-C16/C18 (60:40) were verified using 25 % total surfactant concentration and storage at 5 °C for 12 weeks. MES/APG-based surfactant systems have promising potential in hair shampoo applications, because both surfactants have low skin irritation potentials and are produced from renewable raw materials."
Background Platelet-activating factor (PAF) has been suggested to be a potent inflammatory mediat... more Background Platelet-activating factor (PAF) has been suggested to be a potent inflammatory mediator in Allergic rhinitis (AR) pathogenesis. Vitamin E, an essential nutrient that comprises tocopherol and tocotrienol, is known as a potential therapeutic agent for airway allergic inflammation. This study aimed to investigate the beneficial effects of intranasal Tocotrienol-rich fraction (TRF) on PAF-induced AR in a rat model. Methods Sprague Dawley rats were randomly assigned into 3 groups: Control, PAF-induced AR and PAF-induced AR with TRF treatment. To induce AR, 50 μl of 16 μg/ml PAF was nasally instilled into each nostril. From day 1 to 7 after AR induction, 10 μl of 16 μg/μl TRF was delivered intranasally to the TRF treatment group. Complete upper skulls were collected for histopathological evaluation on day 8. Results The average severity scores of AR were significantly higher in the PAF-induced AR rats compared to both control and PAF-induced AR with TRF treatment. The histolog...
Background: Platelet-activating factor (PAF) has been suggested to be a potent inflammatory media... more Background: Platelet-activating factor (PAF) has been suggested to be a potent inflammatory mediator in Allergic rhinitis (AR) pathogenesis. Vitamin E is known as a potential therapeutic agent for airway allergic inflammation. This study aimed to investigate the beneficial effects of palm-derived Tocotrienol-rich fraction (TRF) on PAF-induced AR in a rat model. Methods: Sprague Dawley rats were randomly assigned into 3 groups: Control, PAF-induced AR and PAF-induced AR with TRF treatment. To induce AR, 50 μl of 16 μg/ml PAF was nasally instilled into each nostril. From day 1 to 7 after AR induction, 10 μl of 16 μg/μl TRF was delivered intranasally to the TRF treatment group. Complete upper skulls were collected for histopathological evaluation on day 8.Results: The average severity scores of AR were significantly higher in the PAF-induced AR rats compared to both control and PAF-induced AR with TRF treatment. The histologic examination of the nasal structures showed moderate degree ...
Background: Oxidative stress and inflammation are some of the proposed mechanisms involved in the... more Background: Oxidative stress and inflammation are some of the proposed mechanisms involved in the pathogenesis of atopic dermatitis (AD). Current pharmacotherapeutic approaches are effective yet they are not without adverse effects. Vitamin E has great potential as an adjunctive treatment for AD owing to its antioxidant and anti-inflammatory bioactivities. Summary: This review article summarizes the current available evidence from cellular, animal and clinical studies on the relationship between vitamin E and AD. The future prospects of vitamin E are also discussed. Vitamin E in practice does not show any toxicity to humans within a range of reasonable dosage. Albeit rarely, vitamin E as a contact allergen should be considered. Collectively, this review envisaged vitamin E as an adjunctive treatment for AD patients. Future research on the distinct effects of different vitamin E isoforms as well as their delivery system in skin disorders is needed.
Hypothesis: Many ionic surfactants with wide applications in personal-care and household detergen... more Hypothesis: Many ionic surfactants with wide applications in personal-care and household detergency show limited water solubility at lower temperatures (Krafft point). This drawback can be overcome by using mixed solutions, where the ionic surfactant is incorporated in mixed micelles with another surfactant, which is soluble at lower temperatures. Experiments: The solubility and electrolytic conductivity for a binary surfactant mixture of anionic methyl ester sulfonates (MES) with nonionic alkyl polyglucoside and alkyl polyoxyethylene ether at 5 C during long-term storage were measured. Phase diagrams were established; a general theoretical model for their explanation was developed and checked experimentally. Findings: The binary and ternary phase diagrams for studied surfactant mixtures include phase domains: mixed micelles; micelles + crystallites; crystallites, and molecular solution. The proposed general methodology, which utilizes the equations of molecular thermodynamics at minimum number of experimental measurements, is convenient for construction of such phase diagrams. The results could increase the range of applicability of MES-surfactants with relatively high Krafft temperature, but with various useful properties such as excellent biodegradability and skin compatibility; stability in hard water; good wetting and cleaning performance.
Here, we present results from a systematic study on cleaning of oily deposits from solid surfaces... more Here, we present results from a systematic study on cleaning of oily deposits from solid surfaces (porcelain and stainless steel) by solutions of fatty acid sulfonated methyl esters (SME), sodium salts. The zwitterionic dodecyldimethylamine oxide (DDAO) has been used as a cosurfactant. As representatives of the vegetable and mineral oils, sunflower seed oil and light mineral oil have been used. The process of oil drop detachment from the solid substrates (roll-up mechanism) has been monitored. In the case of porcelain, excellent cleaning of oil is achieved by mixed solutions of SME and DDAO. In the case of stainless steel, excellent cleaning (superior than that by linear alkylbenzene sulfonate and sodium lauryl ether sulfate) is provided by binary and ternary mixtures of SMEs, which may contain also DDAO. For the studied systems, the good cleaning correlates neither with the oil/water interfacial tension, nor with the surfactant chainlength and headgroup type. The data imply that governing factors might be the thickness and morphology of admicelle layers formed on the solid/water interface. The results indicate that the SME mixtures represent a promising system for formulations in household detergency, having in mind also other useful properties of SME, such as biodegradability, skin compatibility and hard water tolerance.
This is a review article on the rheological properties of mixed solutions of sulfonated methyl es... more This is a review article on the rheological properties of mixed solutions of sulfonated methyl esters (SME) and cocamidopropyl betaine (CAPB), which are related to the synergistic growth of giant micelles. Effects of additives, such as fatty alcohols, cocamide monoethanolamine (CMEA) and salt, which are expected to boost the growth of wormlike micelles, are studied. We report and systematize the most significant observed effects with an emphasis on the interpretation at molecular level and understanding the rheological behavior of these systems. The experiments show that the mixing of SME and CAPB produces a significant rise of viscosity, which is greater than in the mixed solutions of sodium dodecyl sulfate and CAPB. The addition of fatty alcohols, CMEA and cationic polymer, leads to broadening of the synergistic peak in viscosity without any pronounced effect on its height. The addition of NaCl leads to a typical salt curve with high maximum, but in the presence of dodecanol this maximum is much lower. At lower salt concentrations, the fatty alcohol acts as a thickener, whereas at higher salt concentrations-as a thinning agent. Depending on the shape of the frequency dependences of the measured storage and loss moduli, G' and G", the investigated micellar solutions behave as systems of standard or nonstandard rheological behavior. The systems with standard behavior obey the Maxwell viscoelastic model (at least) up to the crossover point (G' = G") and can be analyzed in terms of the Cates reptationreaction model. The systems with nonstandard rheological behavior obey the Maxwell model only in a restricted domain below the crossover frequency; they can be analyzed in the framework of an augmented version of the Maxwell model. The methodology for data analysis and interpretation could be applied to any other viscoelastic micellar system.
Colloids and Surfaces A: Physicochemical and Engineering Aspects, 2019
The deposition of oil drops on solid substrates from mixed solutions of surfactants and cationic ... more The deposition of oil drops on solid substrates from mixed solutions of surfactants and cationic polymer is investigated. The used anionic surfactants are sodium laurylethersulfate (SLES) and sulfonated methyl esters (SME); the zwitterionic surfactant is cocamidopropyl betaine (CAPB). A new method, called the pressed drop method (PDM), was proposed to study the drop adhesion to substrates of different hydrophobicity. The PDM allows one to detect the presence or absence of drop adhesion at different degrees of dilution of the initial solution and, thus, to determine the threshold concentration of drop adhesion. The results show that the increase of the fraction of CAPB in the mixture with the anionic surfactant suppresses the oil-drop deposition; SME provides easier drop adhesion than SLES; the addition of NaCl enhances, whereas coco-fatty-acid-monoethanolamide (CMEA) suppresses the drop deposition; no drop adhesion is observed in the absence of polymer. The drop-tosubstrate adhesion is interpreted in terms of the acting surface forces: polymer bridging attraction; hydrophobic attraction between segments of adsorbed polymer brushes and electrostatic forces. From viewpoint of applications, the PDM experiments enable one to compare the performance of various components in personal care formulations and to optimize their composition with respect to the oil-drop deposition.
Hypotheses: The micellar solutions of sulfonated methyl esters (SME) are expected to form stratif... more Hypotheses: The micellar solutions of sulfonated methyl esters (SME) are expected to form stratifying foam films that exhibit stepwise thinning. From the height of the steps, which are engendered by micellar layers confined in the films, we could determine the micelle aggregation number, surface electric potential, and ionization degree. Moreover, addition of the zwitterionic surfactant cocamidopropyl betaine (CAPB) is expected to transform the small spherical micelles of SME into giant wormlike aggregates. Experiments: Stratifying films from SME solutions are formed and the heights of the steps are recorded. The viscosity of mixed SME + CAPB solutions is measured at various concentrations and weight ratios of the two surfactants. Findings: By theoretical analysis of the foam film data, we established that at 30-100 mM SME spherical micelles are formed and their aggregation number was determined. The addition of calcium ions, as in hard water, does not produce significant effect. However, SME and CAPB exhibit a strong synergism with respect to micelle growth as indicated by the high solution's viscosity. For this reason, the SME + CAPB mixtures represent a promising system for formulations in personal-care and household detergency, having in mind also other useful properties of SME, such as high hard water tolerance, biodegradability and skin compatibility.
The detergency performance of α-sulfo fattymethyl ester sulfonate (α-MES) under different water h... more The detergency performance of α-sulfo fattymethyl ester sulfonate (α-MES) under different water hardness conditions was compared against the dominant workhorse in Home Care products, linear alkylbenzene sulfonate (LAS). Results demonstrate that α-MES has a higher soil removal index and its detergency performance is not drastically affected by water hardness, compared to that of LAS. The addition of α-MES to LAS also shows an improved cleaning performance and better water hardness resistance, due to the structural characteristics of α-MES, which allow the molecules to be relatively insensitive toward polyvalent ions such as Ca 2+ and Mg 2+. The washing performance of α-MES, α-MES/LAS, and LAS with different builders at various dosages was studied, and the results indicated that the dosage of builders in the detergent product could be reduced up to 33% with the application of α-MES, while the detergency is not sacrificed.
Proceedings of 2022 AOCS Annual Meeting & Expo
"Methyl ester sulphonates (MES), which are produced from renewable vegetable oil-based mater... more "Methyl ester sulphonates (MES), which are produced from renewable vegetable oil-based materials and have an ISO 16128 natural origin index of 0.84, are promising new surfactants for conditioning hair shampoos. Previous studies have shown that MES has low skin irritation potential (i.e., mild to the skin), provides easier deposition of conditioning agents compared to sodium lauryl ether sulphate (SLES), and readily delivers desired rheology profiles. A drawback of MES is that it has poor solubility at low temperatures. The Krafft temperatures (TK) of MES-C16 and MES-C18 are 28 °C and 41 °C, respectively, which can be lowered substantially by using eutectic mixtures of MES-C16 and MES-C18; for example, MES-C16/C18 (3:1, w/w) has a TK of 15 °C. At temperatures below 15 °C, all mixtures of MES-C16 and MES-C18 are turbid due to the formation of MES crystals, and phase separation could occur during long-term storage. The solubility of MES could be further improved by incorporating the MES molecules into the micelles of other surfactants. In this study, the solubility of MES in pure water at 5 °C in the presence of alkyl polyglucosides (APG) was investigated. The results showed that the solubility of MES improved by > 28 times in the presence of APG at low total surfactant concentrations and predicts that at higher total surfactant concentrations, solutions of MES and APG will remain transparent at 5 °C when the weight fraction of MES-C16, MES-C18, MES-C16/C18 (80:20), and MES-C16/C18 (60:40) are below 28 %, 15 %, 35 %, and 38 %, respectively. Predictions for MES-C16/C18 (80:20) and MES-C16/C18 (60:40) were verified using 25 % total surfactant concentration and storage at 5 °C for 12 weeks. MES/APG-based surfactant systems have promising potential in hair shampoo applications, because both surfactants have low skin irritation potentials and are produced from renewable raw materials."
Background Platelet-activating factor (PAF) has been suggested to be a potent inflammatory mediat... more Background Platelet-activating factor (PAF) has been suggested to be a potent inflammatory mediator in Allergic rhinitis (AR) pathogenesis. Vitamin E, an essential nutrient that comprises tocopherol and tocotrienol, is known as a potential therapeutic agent for airway allergic inflammation. This study aimed to investigate the beneficial effects of intranasal Tocotrienol-rich fraction (TRF) on PAF-induced AR in a rat model. Methods Sprague Dawley rats were randomly assigned into 3 groups: Control, PAF-induced AR and PAF-induced AR with TRF treatment. To induce AR, 50 μl of 16 μg/ml PAF was nasally instilled into each nostril. From day 1 to 7 after AR induction, 10 μl of 16 μg/μl TRF was delivered intranasally to the TRF treatment group. Complete upper skulls were collected for histopathological evaluation on day 8. Results The average severity scores of AR were significantly higher in the PAF-induced AR rats compared to both control and PAF-induced AR with TRF treatment. The histolog...
Background: Platelet-activating factor (PAF) has been suggested to be a potent inflammatory media... more Background: Platelet-activating factor (PAF) has been suggested to be a potent inflammatory mediator in Allergic rhinitis (AR) pathogenesis. Vitamin E is known as a potential therapeutic agent for airway allergic inflammation. This study aimed to investigate the beneficial effects of palm-derived Tocotrienol-rich fraction (TRF) on PAF-induced AR in a rat model. Methods: Sprague Dawley rats were randomly assigned into 3 groups: Control, PAF-induced AR and PAF-induced AR with TRF treatment. To induce AR, 50 μl of 16 μg/ml PAF was nasally instilled into each nostril. From day 1 to 7 after AR induction, 10 μl of 16 μg/μl TRF was delivered intranasally to the TRF treatment group. Complete upper skulls were collected for histopathological evaluation on day 8.Results: The average severity scores of AR were significantly higher in the PAF-induced AR rats compared to both control and PAF-induced AR with TRF treatment. The histologic examination of the nasal structures showed moderate degree ...
Background: Oxidative stress and inflammation are some of the proposed mechanisms involved in the... more Background: Oxidative stress and inflammation are some of the proposed mechanisms involved in the pathogenesis of atopic dermatitis (AD). Current pharmacotherapeutic approaches are effective yet they are not without adverse effects. Vitamin E has great potential as an adjunctive treatment for AD owing to its antioxidant and anti-inflammatory bioactivities. Summary: This review article summarizes the current available evidence from cellular, animal and clinical studies on the relationship between vitamin E and AD. The future prospects of vitamin E are also discussed. Vitamin E in practice does not show any toxicity to humans within a range of reasonable dosage. Albeit rarely, vitamin E as a contact allergen should be considered. Collectively, this review envisaged vitamin E as an adjunctive treatment for AD patients. Future research on the distinct effects of different vitamin E isoforms as well as their delivery system in skin disorders is needed.
Hypothesis: Many ionic surfactants with wide applications in personal-care and household detergen... more Hypothesis: Many ionic surfactants with wide applications in personal-care and household detergency show limited water solubility at lower temperatures (Krafft point). This drawback can be overcome by using mixed solutions, where the ionic surfactant is incorporated in mixed micelles with another surfactant, which is soluble at lower temperatures. Experiments: The solubility and electrolytic conductivity for a binary surfactant mixture of anionic methyl ester sulfonates (MES) with nonionic alkyl polyglucoside and alkyl polyoxyethylene ether at 5 C during long-term storage were measured. Phase diagrams were established; a general theoretical model for their explanation was developed and checked experimentally. Findings: The binary and ternary phase diagrams for studied surfactant mixtures include phase domains: mixed micelles; micelles + crystallites; crystallites, and molecular solution. The proposed general methodology, which utilizes the equations of molecular thermodynamics at minimum number of experimental measurements, is convenient for construction of such phase diagrams. The results could increase the range of applicability of MES-surfactants with relatively high Krafft temperature, but with various useful properties such as excellent biodegradability and skin compatibility; stability in hard water; good wetting and cleaning performance.
Here, we present results from a systematic study on cleaning of oily deposits from solid surfaces... more Here, we present results from a systematic study on cleaning of oily deposits from solid surfaces (porcelain and stainless steel) by solutions of fatty acid sulfonated methyl esters (SME), sodium salts. The zwitterionic dodecyldimethylamine oxide (DDAO) has been used as a cosurfactant. As representatives of the vegetable and mineral oils, sunflower seed oil and light mineral oil have been used. The process of oil drop detachment from the solid substrates (roll-up mechanism) has been monitored. In the case of porcelain, excellent cleaning of oil is achieved by mixed solutions of SME and DDAO. In the case of stainless steel, excellent cleaning (superior than that by linear alkylbenzene sulfonate and sodium lauryl ether sulfate) is provided by binary and ternary mixtures of SMEs, which may contain also DDAO. For the studied systems, the good cleaning correlates neither with the oil/water interfacial tension, nor with the surfactant chainlength and headgroup type. The data imply that governing factors might be the thickness and morphology of admicelle layers formed on the solid/water interface. The results indicate that the SME mixtures represent a promising system for formulations in household detergency, having in mind also other useful properties of SME, such as biodegradability, skin compatibility and hard water tolerance.
This is a review article on the rheological properties of mixed solutions of sulfonated methyl es... more This is a review article on the rheological properties of mixed solutions of sulfonated methyl esters (SME) and cocamidopropyl betaine (CAPB), which are related to the synergistic growth of giant micelles. Effects of additives, such as fatty alcohols, cocamide monoethanolamine (CMEA) and salt, which are expected to boost the growth of wormlike micelles, are studied. We report and systematize the most significant observed effects with an emphasis on the interpretation at molecular level and understanding the rheological behavior of these systems. The experiments show that the mixing of SME and CAPB produces a significant rise of viscosity, which is greater than in the mixed solutions of sodium dodecyl sulfate and CAPB. The addition of fatty alcohols, CMEA and cationic polymer, leads to broadening of the synergistic peak in viscosity without any pronounced effect on its height. The addition of NaCl leads to a typical salt curve with high maximum, but in the presence of dodecanol this maximum is much lower. At lower salt concentrations, the fatty alcohol acts as a thickener, whereas at higher salt concentrations-as a thinning agent. Depending on the shape of the frequency dependences of the measured storage and loss moduli, G' and G", the investigated micellar solutions behave as systems of standard or nonstandard rheological behavior. The systems with standard behavior obey the Maxwell viscoelastic model (at least) up to the crossover point (G' = G") and can be analyzed in terms of the Cates reptationreaction model. The systems with nonstandard rheological behavior obey the Maxwell model only in a restricted domain below the crossover frequency; they can be analyzed in the framework of an augmented version of the Maxwell model. The methodology for data analysis and interpretation could be applied to any other viscoelastic micellar system.
Colloids and Surfaces A: Physicochemical and Engineering Aspects, 2019
The deposition of oil drops on solid substrates from mixed solutions of surfactants and cationic ... more The deposition of oil drops on solid substrates from mixed solutions of surfactants and cationic polymer is investigated. The used anionic surfactants are sodium laurylethersulfate (SLES) and sulfonated methyl esters (SME); the zwitterionic surfactant is cocamidopropyl betaine (CAPB). A new method, called the pressed drop method (PDM), was proposed to study the drop adhesion to substrates of different hydrophobicity. The PDM allows one to detect the presence or absence of drop adhesion at different degrees of dilution of the initial solution and, thus, to determine the threshold concentration of drop adhesion. The results show that the increase of the fraction of CAPB in the mixture with the anionic surfactant suppresses the oil-drop deposition; SME provides easier drop adhesion than SLES; the addition of NaCl enhances, whereas coco-fatty-acid-monoethanolamide (CMEA) suppresses the drop deposition; no drop adhesion is observed in the absence of polymer. The drop-tosubstrate adhesion is interpreted in terms of the acting surface forces: polymer bridging attraction; hydrophobic attraction between segments of adsorbed polymer brushes and electrostatic forces. From viewpoint of applications, the PDM experiments enable one to compare the performance of various components in personal care formulations and to optimize their composition with respect to the oil-drop deposition.
Hypotheses: The micellar solutions of sulfonated methyl esters (SME) are expected to form stratif... more Hypotheses: The micellar solutions of sulfonated methyl esters (SME) are expected to form stratifying foam films that exhibit stepwise thinning. From the height of the steps, which are engendered by micellar layers confined in the films, we could determine the micelle aggregation number, surface electric potential, and ionization degree. Moreover, addition of the zwitterionic surfactant cocamidopropyl betaine (CAPB) is expected to transform the small spherical micelles of SME into giant wormlike aggregates. Experiments: Stratifying films from SME solutions are formed and the heights of the steps are recorded. The viscosity of mixed SME + CAPB solutions is measured at various concentrations and weight ratios of the two surfactants. Findings: By theoretical analysis of the foam film data, we established that at 30-100 mM SME spherical micelles are formed and their aggregation number was determined. The addition of calcium ions, as in hard water, does not produce significant effect. However, SME and CAPB exhibit a strong synergism with respect to micelle growth as indicated by the high solution's viscosity. For this reason, the SME + CAPB mixtures represent a promising system for formulations in personal-care and household detergency, having in mind also other useful properties of SME, such as high hard water tolerance, biodegradability and skin compatibility.
The detergency performance of α-sulfo fattymethyl ester sulfonate (α-MES) under different water h... more The detergency performance of α-sulfo fattymethyl ester sulfonate (α-MES) under different water hardness conditions was compared against the dominant workhorse in Home Care products, linear alkylbenzene sulfonate (LAS). Results demonstrate that α-MES has a higher soil removal index and its detergency performance is not drastically affected by water hardness, compared to that of LAS. The addition of α-MES to LAS also shows an improved cleaning performance and better water hardness resistance, due to the structural characteristics of α-MES, which allow the molecules to be relatively insensitive toward polyvalent ions such as Ca 2+ and Mg 2+. The washing performance of α-MES, α-MES/LAS, and LAS with different builders at various dosages was studied, and the results indicated that the dosage of builders in the detergent product could be reduced up to 33% with the application of α-MES, while the detergency is not sacrificed.
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